Hand-made Almost Ready to Fly R/C Model Aircraft ASSEMBLY MANUAL Specifications

SPORTS TRAINER - ENGINE SIZE.40 - .46 - 2STROKE
Hand-made Almost Ready to Fly R/C Model Aircraft
ASSEMBLY MANUAL
Specifications
Wingspan _____________________________ 155cm.
Wing area _________________________ 3950 sq cm .
Approximate flying weight _______________ 2.6-2.8kg.
Recommended engine size 0.40-0.46 cu. ins 2-stroke.
Recommended R/C ___________ 4 channel minimum.
Flying skill level ___________________ Sports Trainer.
Additional items required.
Engine.
4 Channel or greater Radio Control system.
Glues.
Tools.
Starting Equipment.
Kit features.
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Ready-made—minimal assembly & finishing required.
Ready-covered—including decals, trim & covering.
Factory-installed pushrod.
Factory-pinned & glued control surface hinges for ultimate safety.
Comprehensive hardware pack including wheels, tank, spats,undercarriage& spinner.
Photo-illustrated step-by-step Assembly Manual.
Made in Vietnam.
BOOMERANG 40.
Instruction Manual.
INTRODUCTION.
Thank you for choosing the Boomerang 40 ARTF by SEAGULL MODELS. The Boomerang 40 was
designed with the sports trainer flyer in mind. It is a High-wing aeroplane which is easy to fly and
quick to assemble. The airframe is conventionally built using balsa, plywood and veneer to make it
stronger than the average ARTF , yet the design allows the aeroplane to be kept light. You will find
that most of the work has been done for you already. The pushrods are pre-made to the correct
lengths, the motor mount has been fitted and the hinges are pre-installed and pinned for security.
Flying the Boomerang 40 is simply a joy.
This instruction manual is designed to help you build a great flying aeroplane. Please read this
manual throughly before starting assembly of your Boomerang 40 . Use the parts listing below to
identify all parts.
WARNING.
Please be aware that this aeroplane is not a toy and if assembled or used incorrectly it is capable
of causing injury to people or property. WHEN YOU FLY THIS AEROPLANE YOU ASSUME ALL
RISK & RESPONSIBILITY.
If you are inexperienced with basic R/C flight we strongly recommend you contact your R/C supplier
and join your local R/C Model Flying Club. R/C Model Flying Clubs offer a variety of training
procedures designed to help the new pilot on his way to successful R/C flight. They will also be able
to advise on any insurance and safety regulations that may apply.
ADDITIONAL ITEMS REQUIRED.
- .40-.46 2-stroke engine.
- 4 channel radio with four servos.
- Glow plug to suit engine.
- Propeller to suit engine.
- Protective foam rubber for radio
system.
- Silicone fuel line.
- Stick-on weights for balance
(If necessary).
TOOLS & SUPPLIES NEEDED.
- Thick cyanoacrylate glue.
- 30 minute epoxy.
- 5 minute epoxy.
- Hand or electric drill.
- Assorted drill bits.
- Modelling knife.
- Straight edge ruler.
- 2mm ball driver.
- Phillips head screwdriver.
- 220 grit sandpaper.
- 90° square or builder’s triangle.
- Wire cutters.
- Masking tape & T-pins.
- Thread-lock.
- Paper towels.
2
PARTS LISTING.
FUSELAGE ASSEMBLY
- (1) Fuselage.
- (1) Pre-installed throttle pushrod &
tube.
- (1) Pre-installed servo tray.
- (1) Pre-installed motor mount.
- (1) Pre-installed rudder pushrod.
- (1) Pre-installed elevator pushrod.
WING ASSEMBLY
- (1) Right wing half with preinstalled aileron.
- (1) Left wing half with pre-installed
aileron.
- (1) Plywood wing dihedral brace.
- (1) Covering strip for centre
section joint.
TAIL SECTION ASSEMBLY
- (1) Vertical stabilizer with preinstalled rudder.
- (1) Horizontal stabilizer with preinstalled elevator halves.
BOOMERANG 40.
NOTE: To avoid scratching your new aeroplane we suggest that you cover
your workbench with an old towel.
Keep a couple of jars or bowls handy
to hold the small parts after you open
the bags.
Please trial fit all parts. Make sure
you have the correct parts and that
they fit and are aligned properly before gluing! This will ensure proper
assembly as the Boomerang 40 is
made from natural materials and
minor adjustments may have to be
made.
The paint and plastic parts used in
this kit are fuel proof. However, they
are not tolerant of many harsh chemicals including the following: paint
thinner, cyano-acrylate glue accelerator, cyanoacrylate glue de-bonder
and acetone. Do not let these chemicals come in contact with the colours
on the covering and the plastic parts.
Instruction Manual.
WING ASSEMBLY.
NOTE: We highly recommend using 30
minute epoxy as it is stronger and provides
more working time, allowing the builder to
properly align the parts. Using fast cure epoxy
when joining the wing halves could result in the
glue drying before the wing halves are aligned
properly which may result in failure of the wing
centre section during flight.
1) Test fit the wing tube into each wing half.
The brace should slide in easily up to the
centreline that you drew.If not, use 220 grit
sandpaper with a sanding block and sand
down the edges and ends of the brace until it
fits properly.
Centre line.
Masking tape.
Expoxy.
2) Remove the brace when satisfied with
its fit ineach wing half. Coat both sides of one
half of the dihedral brace with 30 minute epoxy.
Next, pour some epoxy into the dihedral box in
one wing panel. Make sure you cover the top
and bottom as well as the sides of the dihedral
brace. Use enough epoxy to fill any gaps.
Carefully slide the two wing halves together
and firmly press them together, allowing the
excess epoxy to run out. There should not be
any gap in the wing halves. Use rubbing
alcohol and a paper tower to clean up any
excess epoxy.
Apply masking tape at the wing join to hold
the wing halves together securely.
3
BOOMERANG 40.
3) Peel off the backing from the self adhesive covering strip. Apply the strip to the centre
section of the wing starting from the bottom
trailing edge. Wrap the strip all the way around
the wing until it meets the trailing edge again.
Trim off any excess strip.
Instruction Manual.
8.
Peel off the backing from the self
adhesive covering strip. Apply the strip to the
centre section of the wing starting from the
bottom trailing edge. Wrap the strip all the way
around the wing until it meets the trailing edge
again. Trim off any excess strip.
INSTALLING THE AILERON SERVO MOUNT.
1. Install the rubber grommets and brass
collets onto the aileron servo. Test fit the servo
into the aileron servo mount.
Epoxy attach.
4.
Once the epoxy has cured, trial fit
both wing halves together. The centre ribs
should fit together flush with no gaps. If gaps do
exist, use 220 grit sandpaper and sand down
the high spots on the root ribs and the wing
joiner until a proper fit is achieved. The correct
amount of dihedral is ready-built into the wings.
With one wing half laid flat on the table, the
other wing tip should be off the table surface.
If this needs to be adjusted, you may do so by
sanding small amounts from the centre ribs or
dihedral brace.
5.
Carefully apply masking tape around
the top and bottom edge of the root rib of each
wing half to protect them from damage caused
by epoxy.
6.
Mix a generous amount of 30 minute
epoxy. Coat the exposed half of the dihedral
brace, and the remaining wing joiner box and
both root ribs with epoxy. Slide the two wing
halves together and carefully align them at the
leading and trailing edges. Wipe away any
excess epoxy using paper towels. Use masking tape wrapped around the centre section to
hold the halves in place until the epoxy cures.
7.
When the epoxy has cured, carefully
remove the masking tape from the wing.
4
Because the size of servos differ, you
may need to adjust the size of the precut
opening in the mount. The notch in the sides
of the mount allow the servo lead to pass
through.
2. Remove the aileron servo. Place the
mount onto the wing, aligning the cutout in the
mount with the cutout in the wing. The two
notches in the mount should face the leading
edge of the wing.
3. While holding the servo mount firmly
in place, trace around it using a pen.
4. Remove the mount, and using a modeling knife, carefully remove the covering from
inside the outline you drew.
5. Using 6 Minute Epoxy, glue the servo
mount into place. Remove any excess epoxy
using a paper towel and rubbing alcohol. Use
pieces of masking tape to hold the tray in place
until the epoxy fully cures.
Servo tray.
BOOMERANG 40.
INSTALLING THE AILERON SERVO.
Install the aileron servo into the servo
mount, with the output shaft towards the leading edge of the wing, using the wood screws
provided with your radio system. Drill 1/16”
pilot holes through the mount before installing
the screws. This will prevent the wood from
splitting.
Instruction Manual.
4. Slide the pushrod wires following picture above.
5. With both the aileron servo and the ailerons centered. Tighten the set screws on the
connectors.
INSTALLING THE MAIN GEAR WIRES.
1. Using a modeling knife, remove the
covering from over the two main gear mounting slots located in the bottom of the fuselage.
Remove covering.
INSTALLING THE AILERON LINKAGE.
1. Thread one nylon adjustable control
horn onto each aileron torque rod. Thread
the horns on until they are flush with the ends
of the torque rods.
2. Thread one nylon clevis at least 5/16”
onto each of the two threaded wires.
3. With the aileron servo centered, install
the servo arm onto the servo. The arm should
be installed so it is parallel with the trailing edge
of the wing.
2. Using the two landing gear straps as a
guide, mark the locations of the four 3mm x
12mm mounting screws onto the fuselage surface.
3. The landing gear wire is held in place
using two nylon landing gear straps and four
3mm x 12mm wood screws.
The straps should be located equal distance
from the inside and outside ends of the wire.
Pen.
C/A glue fix.
Connector.
Pushrod
wire.
Plastic trap.
4. Insert the main gear wire into the
mounting slot.
5. Remove the two straps and the gear
wire. Drill four 3/32” pilot holes into the fuselage for the wood screws.
5
BOOMERANG 40.
2mm.
Instruction Manual.
Steering arm.
Adjust the nose gear steering arm until the
arm is parallel with the fire wall.
Steering arm.
3mm X 12mm.
Pushrod wire.
NOSE GEAR INSTALLATION.
FUEL TANK.
INSTALLING THE STOPPER ASSEMBLY.
1. Using a modeling knife, carefully cut
off the rear portion of one of the two nylon tubes
leaving 1/2” protruding from the rear of the
stopper. This will be the fuel pick up tube.
2. Using a modeling knife, cut one length
of silicon fuel line (not included) to 2-1/4” long.
Connect one end of the line to the weighted
fuel pickup and the other end to the nylon
pickup tube.
TOOLS REQUIRED
Installing steering arm as follow.
6
3. Carefully bend the second nylon tube
up at a 45º angle. This tube is the vent tube.
BOOMERANG 40.
Instruction Manual.
Top of tank.
Vent tube.
4. Carefully heat the vent tube using a
heat gun or lighter to permanently set the
angle of the tube.
Vent tube.
Fuel Pickup
Tube.
Fuel fill tube.
Fuel pickup tube.
INSTALLING THE FUEL TANK.
Fuel Fill Tube.
Pushrod wire.
When the stopper assembly is installed in
the tank, the top of the vent tube should rest
just below the top surface of the tank. It should
not touch the top of the tank.
5. Test fit the stopper assembly into the
tank. It may be necessary to remove some of
the flashing around the tank opening using a
modeling knife. If flashing is present, make
sure none falls into the tank.
Plastic tape.
6. With the stopper assembly in place,
the weighted pickup should rest about 3/8”
away from the rear of the tank and move freely
inside the tank. The top of the vent tube should
rest just below the top of the tank. It should
not touch the top of the tank.
7. When satisfied with the alignment of
the stopper assembly tighten the 3mm x 20mm
machine screw until the rubber stopper expands and seals the tank opening. Do not
overtighten the assembly as this could cause
the tank to split.
Pull.
7
BOOMERANG 40.
2. Use pieces off foam rubber to hold the
tank in place. Be careful the tank or the foam
doesn’t interfere with the pushrods. Cut the
fuel line in the middle of the loop. Keep track
of which one is for the fuel pick-up and which
one is for the muffler pressure.
Blow through the tubes to make sure the
lines have not become kinked during
installation.
Instruction Manual.
2. Place your engine onto the engine
mount. Adjust the engine is centered of the
edges of the engine case.
3. When you are satisfied with the alignment, mark the locations of the engine
mounting.
4. Remove the engine. Using an drill bit,
drill the mounting holes through the engine
mount at the four locations marked.
2.5mm.
3mm X 25mm.
Fuel tank.
Vent tube.
Fuel pickup
tube.
Fuel fill tube.
MOUNTING THE ENGINE.
PARTS REQUIRED.
5. Bolt the engine to the engine mount
using the four machine screws. Double
cheek that all the screws are tight before
proceeding.
6. Attach the Z-Bend in the pushrod wire
to the throttle arm on the carburetor. You will
need to remove the throttle arm from the carburetor to be able to attach the Z-bend. When
complete, reattach the throttle arm to the carburetor.
1. Install the pushrod housing through the
predrilled hole in the firewall and into the servo
compartment. The pushrod housing should
protrude 1/4" out past the front of the firewall.
Make a Z-Bend 1/4" from one end of the plain
wire pushrod.
Pushrod wire.
110mm.
8
BOOMERANG 40.
INSTALLING THE SPINNER.
Instruction Manual.
INSTALLING THE FUSELAGE SERVOS.
Install the spinner backplate, propeller and
spinner cone. The spinner cone is held in
place using two 3mm x 12mm wood screws.
Rudder servo.
The propeller should not touch any part
of the spinner cone. If it does, use a sharp
modeling knife and carefully trim away the
spinner cone where the propeller comes in
contact with it.
Elevator servo.
Throttle servo.
HORIZONTAL STABILIZER.
1. Using a ruler and a pen, locate the
centerline of the horizontal stabilizer, at the
trailing edge, and place a mark. Use a triangle and extend this mark, from back to front,
across the top of the stabilizer. Also extend
this mark down the back of the trailing edge
of the stabilizer.
Draw centerline.
INSTALLING THE SWITCH.
Install the switch into the precut hole in the
servo tray, in the fuselage, from the bottom.
Use the two screws provided with the switch
to secure it in place. Drill two 3/32” holes
through the tray for the screws to pass
through.
The top of the stabilizer does not have
the hinge pins exposed.
2. Using a modeling knife, carefully remove the covering from over the vertical stabilizer mounting slot in the top of the fuselage.
Remove covering.
Switch.
3. Slide the stabilizer into place in the precut slot in the rear of the fuselage. The stabilizer should be pushed firmly against the front
of the slot.
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BOOMERANG 40.
Instruction Manual.
4. With the stabilizer held firmly in place,
use a pen and draw lines onto the stabilizer
where it and the fuselage sides meet. Do this
on both the right and left sides and top and
bottom of the stabilizer.
Pen.
5. Remove the stabilizer. Using the lines
you just drew as a guide, carefully remove the
covering from between them using a modeling knife.
Remove covering.
When cutting through the covering to remove it, cut with only enough pressure
to only cut through the covering itself. Cutting
into the balsa structure may weaken it.
8. After the epoxy has fully cured, remove the masking tape or T-pins used to hold
the stabilizer in place. Carefully inspect the
glue joints. Use more epoxy to fill in any gaps
that may exist that were not filled previously
and clean up the excess using a paper towel
and rubbing alcohol.
VERTICAL STABILIZER
INSTALLATION.
1. Slide the vertical stabilizer into the slot
in the top of the fuselage. The bottom edge of
the stabilizer should also be firmly pushed
against the top of the horizontal stabilizer.
6. Using a modeling knife, carefully remove the covering that overlaps the stabilizer
mounting platform sides in the fuselage. Remove the covering from both the top and the
bottom of the platform sides.
7. When you are sure that everything is
aligned correctly, mix up a generous amount
of 30 Minute Epoxy. Apply a thin layer to the
top and bottom of the stabilizer mounting area
and to the stabilizer mounting platform sides
in the fuselage. Slide the stabilizer in place
and realign. Double check all of your measurements once more before the epoxy cures.
Hold the stabilizer in place with T-pins or masking tape and remove any excess epoxy using
a paper towel and rubbing alcohol.
10
2. While holding the vertical stabilizer
firmly in place, use a pen and draw a line on
each side of the vertical stabilizer where it
meets the top of the fuselage.
BOOMERANG 40.
Instruction Manual.
the lower hinge also. Set the stabilizer in place
and realign. Double check all of your measurements once more before the epoxy cures. Hold
the stabilizer in place with T-pins or masking
tape and remove any excess epoxy using a
paper towel and rubbing alcohol. Allow the epoxy to fully cure before proceeding.
Pen.
3. Remove the stabilizer. Using a modeling knife, remove the covering from below
the lines you drew. Also remove the covering
from the bottom edge of the stabilizer and the
bottom and top edges of the filler block. Leave
the covering in place on the sides of the filler
block.
CONTROL HORN INSTALLATION.
1. Locate the two nylon control horns, two
nylon control horn backplates and four M2 x
20mm machine screws.
Remove covering.
(2)2mm x 20mm.
When cutting through the covering to remove it, cut with only enough pressure to only
cut through the covering itself. Cutting into
the balsa structure may weaken it.
4. Slide the vertical stabilizer back in
place. Using a triangle, check to ensure that
the vertical stabilizer is aligned 90º to the horizontal stabilizer.
Horizontal
Stabilizer.
90º
2. Position the elevator horn on the bottom
side of elevator. The clevis attachment holes
should be positioned over the hinge line.
Control Horn.
Vertical
Stabilizer.
Mounting Screws.
5. When you are sure that everything is
aligned correctly, mix up a generous amount
of Flash 30 Minute Epoxy. Apply a thin layer to
the mounting slot in the top of the fuselage and
to the sides and bottom of the vertical stabilizer mounting area. Apply epoxy to the bottom and top edges of the filler block and to
Mounting Plate.
3. Using a 1.5mm drill bit and the control
horns as a guide, drill the mounting holes
through the elevator halves.
11
BOOMERANG 40.
Instruction Manual.
Rudder
control horn.
Sanding.
4. Install the rudder control horn using the
same method as with the elevator control
horns.
Cut.
Elevator control horn.
PUSHROD INSTALLATION.
Sanding.
1. Install the elevator pushrod into the fuselage. To help make installation easier, thread
string down through the elevator pushrod exits and into the servo compartment in the fuselage. Tie the thread to the threaded pushrod
wires of the elevator pushrod. Pull the pushrod
through the exit slots.
2. Thread two nylon clevises onto the
threaded wires at least 10 turns. Attach the
clevises to the elevator and rudder control
horns. You may find it necessary to make
slight bends in the wires so they will align with
the control horns without binding.
Control horn.
Cut.
Elevator pushrod.
12
BOOMERANG 40.
Instruction Manual.
Throttle.
Rudder pushrod.
INSTALLING THE MAIN GEAR WHEELS.
Steering pushrod.
Rudder.
1. Slide one wheel collar with 3mm x
6mm set screw onto each axle. Push the
wheel collars on as far as they will go and
tighten the set screws.
Be careful not to overtighten the set
screws. Overtightening may cause the
threads to strip.
Elevator.
THROTTLE SERVO INSTALLATION.
1. Install adjustable servo connector in the
servo arm.
Adjustable servo connector.
2. Slide one 60mm diameter wheel onto
each axle and push them up against the wheel
collars. Slide the remaining wheel collars with
3mm x 6mm set screws onto the axles. Push
them up against the wheels and tighten the
set screws. The wheels should spin free and
not bind in any way. If they do bind, loosen the
set screws in the outer wheel collars and move
the collars out a small amount. Retighten the
set screws.
C/A glue fix.
Servo arm.
2. Install the rubber grommets and brass
collets onto the throttle servo. Test fit the servo
into the aileron servo mount.
Because the size of servos differ, you may
need to adjust the size of the precut opening
in the mount. The notch in the sides of the
mount allow the servo lead to pass through.
3. Secure the servos with the screws provided with your radio system.
4. Install the pushrod throttle.
INSTALLING THE NOSE GEAR WHEEL.
Slide one 60mm diameter wheel onto the
axle and push them up against the wheel collars. Slide the remaining wheel collars with
3mm x 6mm set screws onto the axles. Push
them up against the wheels and tighten the
set screws. The wheels should spin free and
not bind in any way. If they do bind, loosen the
set screws in the outer wheel collars and move
the collars out a small amount. Retighten the
set screws.
13
BOOMERANG 40.
Instruction Manual.
ATTACHMENT WING-FUSELAGE.
INSTALLING THE RECEIVER AND BATTERY.
See pictures below:
1. Plug the four servo leads and the switch
lead into the receiver. Plug the battery pack
lead into the switch also.
2. Wrap the receiver and battery pack in
the protective foam rubber to protect them
from vibration.
3. Position the battery pack in the fuel tank
compartment and the receiver just behind the
fuel tank . Use extra foam pieces to hold them
in position.
When balancing the airplane you may
need to move the battery or receiver forward or after to achieve proper balance.
4. Using a 1/16” drill bit, drill a hole through
the side of the fuselage, near the receiver, for
the antenna to exit. Route the antenna out of
the fuselage and secure it to the vertical stabilizer using a rubber band and a modified servo
arm. See picture as below.
Cut
Antenna
Modified
Servo Arm
14
Rubber
Band
Dowel.
BOOMERANG 40.
BALANCING.
1. It is critical that your airplane be balanced correctly. Improper balance will cause
your plane to lose control and crash. The center of gravity is located 7.5cm - 8.5cm behind
the leading edge of the wing.
Instruction Manual.
INITIAL FLYING/SPORT FLYING
Ailerons:
Elevator:
Rudder:
3/8” up
3/8” up
1/2” right
3/8” down
3/8” down
1/2” left
AEROBATIC FLYING
2. If the nose of the plane falls, the plane is
nose heavy. To correct this first move the battery pack further back in the fuselage. If this is
not possible or does not correct it, stick small
amounts of lead weight on the fuselage sides
under the horizontal stabilizer. If the tail of the
plane falls, the plane is tail heavy. To correct
this, move the battery and receiver forward orif
this is not possible, stick weight onto the
firewall or use a brass heavy hub spinner hub,
similar to those offered by Harry Higley. When
balanced correctly, the airplane should sit level
or slightly nose down when you lift it up with
your fingers.
Ailerons: 1/2” up
Elevator: 5/8” up
Rudder: 1” right
1/2” down
5/8” down
1” left
Do not use the aerobatic settings for initial test flying or sport flying.
4. By moving the position of the adjustable control horn out from the control surface,
you will decrease the amount of throw of that
control surface. Moving the adjustable control horn toward the control surface will increase the amount of throw.
FLIGHT PREPARATION.
CONTROL THROWS.
1.
We highly recommend setting up the
Boomerang 40 using the control throws listed
at right. We have listed control throws for both
initial test flying/sport flying and aerobatic flying.
2. Turn on the radio system, and with the
trim tabs on the transmitter in neutral, center
the control surfaces by making adjustments
to the clevises or adjustable servo connectors.
The servo arms should be centered also.
3. When the elevator, rudder and aileron
control surfaces are centered, use a ruler and
check the amount of the control throw in each
surface. The control throws should be
measured at the widest point of each surface!
A) Check the operation and direction
of the elevator, rudder, ailerons and throttle.
B) Plug in your radio system per the
manufacture’s instructions and turn every thing
on.
C) Check the elevator first. Pull back
on the elevator stick. The elevator halves
should move up. If it they do not, flip the servo
reversing switch on your transmitter to change
the direction.
D) Check the rudder. Looking from
behind the airplane, move the rudder stick to
the right. The rudder should move to the right.
If it does not, flip the servo reversing switch on
your transmitter to change the direction.
E) Check the throttle. Moving the
throttle stick forward should open the carburetor barrel. If it does not, flip the servo reversing switch on your transmitter to change
the direction.
15
BOOMERANG 40.
F) From behind the airplane, look at
the aileron on the right wing half. Move the
aileron stick to the right. The right aileron
should move up and the other aileron should
move down. If it does not, flip the servo reversing switch on your transmitter to change
the direction.
PREFLIGHT CHECK.
1) Completely charge your transmitter
and receiver batteries before your first day of
flying.
2) Check every bolt and every glue joint
in the Boomerang 40 to ensure that everything is tight and well bonded.
3) Double check the balance of the airplane. Do this with the fuel tank empty.
4) Check the control surfaces. All should
move in the correct direction and not bind in
any way.
5) If your radio transmitter is equipped
with dual rate switches double check that they
are on the low rate setting for your first few
flights.
6) Check to ensure the control surfaces
are moving the proper amount for both low
and high rate settings.
7) Check the receiver antenna. It should
be fully extended and not coiled up inside the
fuselage.
8) Properly balance the propeller. An out
of balance propeller will cause excessive vibration which could lead to engine and/or airframe failure.
We wish you many safe and enjoyable flights with your BOOMERANG 40.
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Instruction Manual.